Consecutive days of heavy smog is nothing new for Koreans. Last year, the country’s air quality at one point reached 179 micrograms per cubic meter of ultrafine dust, the second-highest level in the world after India, according to AirVisual, which measures pollutant levels.

Seoul Mayor Park Won-soon (Yonhap)

But Seoul and its surrounding Gyeonggi Province, where more than half of the country’s 52 million people live, differ sharply in their approach to the issue.

A war of words intensified on both sides after Seoul activated its free public transport program twice this week. Public transportation fees have been waived again for Thursday, as air quality was forecast to remain bad.

During a New Year’s press conference Wednesday at Seoul City Hall, Seoul Metropolitan Government Mayor Park Won-soon urged Gyeonggi Province to follow suit in waiving public transportation fees on days when the air quality is bad, along with other measures to reduce the number of cars on the road on days with high levels of fine dust, saying “It’s better to be overly prepared than not prepared at all.”

“It was the first day on Monday -- and also it was without Gyeonggi Province’s help -- to initiate the free public transport program in Seoul, and more people have participated in today’s free transit campaign,” Park told reporters.

“But what did the governor do on Monday when Gyeonggi Province marked fine dust levels of nearly 100 micrograms per cubic meter, which is worse than Seoul’s 79, besides boycotting the program?” Park asked.

On the question of whether or not he thinks the 1.8 percent reduction in traffic volume as a result of Monday’s program was too low, Park said the figure would grow into the double digits, although he added Gov. Nam Kyung-pil’s participation “would have encouraged more people to use public transportation.”

Currently, Seoul is the only city in the country to waive fees on public transportation when fine particulate matter 2.5 concentration reaches more than 50 micrograms per cubic meter. Gyeonggi Province has refused to follow suit, citing associated costs.

“The issue of citizens’ lives and health should not involve political approaches and the government should take part in carrying out emergency measures,” Mayor Park added.

The aggressive rhetoric came just a day after Nam called Park’s free-ride solution a “populist campaign,” adding the program “wastes” 5 billion won ($4.7 million) of taxpayers’ money every day it is in effect.

At a press conference earlier Tuesday, Nam said the Seoul mayor should end the free transportation program and come up with new measures to fight fine dust particles.

“The money could have been used in other ways to resolve air pollution caused by freight vehicles,” Nam said. According to government data, freight vehicles that run on diesel are responsible for about 70 percent of the country’s vehicular air pollution.

With fine dust reaching unhealthy levels of above 58 micrograms Monday, Seoul activated a new program of measures to fight air pollution -- which also includes temporarily shutting down government building parking lots -- for the first time.

But critics point out that Monday’s program failed to lead to a substantial drop in car use or ultrafine dust density in the capital city.

“The free public transportation program is merely a short-term measure to address the complicated air pollution issue that should consider both domestic and outside factors,” said Kim Ki-hyun, a professor at Hanyang University’s department of Civil and Environmental Engineering.

“More fundamental approaches are needed to mitigate poor air quality, including investigating in air pollution management systems and, most importantly, improving accuracy to measure air quality,” Kim told The Korea Herald.

Over half of the fine dust particles in the country came from abroad in 2016, according to Ministry of Environment’s latest data. As for domestic causes of pollution in Seoul, 39 percent of the fine dust particles came from electricity generated for heating, 37 percent from traffic and 22 percent from construction sites, the data showed.